Method for detecting deterioration defect of structural part using structural unit

Abstract

A method for detecting a deterioration defect of a structural part using a structural unit includes: defining a first base structural unit and obtaining N first base modal parameters of the first base structural unit; detecting a respective one of M first subject structural units of a subject structural part by each of M first sensors to obtain N first actual modal parameters of each of the M first subject structural units; calculating N first subject modal parameters of each of the M first subject structural units according to the N first actual modal parameters of each of the M first subject structural units and M*N first predetermined ratios; and comparing the N first subject modal parameters of each of the M first subject structural units to the N first base modal parameters to determine whether each of the M first subject structural units has a deterioration defect.

What is claimed is: 
     
       1. A method for detecting deterioration defect of a subject structural part, comprising:
 defining a first base structural unit and obtaining N first base modal parameters of the first base structural unit; 
 detecting M first subject structural units included in a subject structural part by M first sensors respectively disposed at the M first subject structural units, so as to obtain N first actual modal parameters of each of the M first subject structural units, wherein the each of the M first subject structural units is identical to the first base structural unit; 
 obtaining M*N first predetermined modal parameters from M first simulated structural units, with each of the M first simulated structural units providing N of the M*N first predetermined modal parameters; 
 dividing the N first base modal parameters respectively by the M*N first predetermined modal parameters to obtain M*N first predetermined ratios; 
 calculating N first subject modal parameters of each of the M first subject structural units by a processor according to the N first actual modal parameters of each of the M first subject structural units and the M*N first predetermined ratios stored in a database, with the processor electrically connected to the M first sensors; and 
 comparing the N first subject modal parameters of each of the M first subject structural units to the N first base modal parameters by the processor, so as to determine whether each of the M first subject structural units has a deterioration defect; 
 wherein each of the M first simulated structural units is identical to the first base structural unit. 
 
     
     
       2. The method for detecting deterioration defect of the structural part according to  claim 1 , further comprising:
 obtaining the M*N first predetermined modal parameters from the M first subject structural units before a first time point, obtaining the N first actual modal parameters of the each of the M first subject structural units at a second time point, with the first time point prior to the second time point for a period of time. 
 
     
     
       3. The method for detecting deterioration defect of the structural part according to  claim 1 , further comprising:
 defining a second base structural unit and obtaining N second base modal parameters of the second base structural unit; 
 detecting a second subject structural unit included in the subject structural part by a second sensor disposed in the subject structural part, so as to obtain N second actual modal parameters of the second subject structural units; 
 calculating N second subject modal parameters of the second subject structural unit by the processor according to the N second actual modal parameters of the second subject structural unit and N second predetermined ratios stored in a database; and 
 comparing the N second subject modal parameters of the second subject structural unit to the N second base modal parameters by the processor, so as to determine whether the second subject structural unit has a deterioration defect; 
 wherein the N second predetermined ratios are related to the N second base modal parameters and N second predetermined modal parameters obtained from a second simulated structural unit, a structural type of the second simulated structural unit is identical to a structural type of the second base structural unit, and the structural type of the second base structural unit is different from the structural type of the first base structural unit. 
 
     
     
       4. The method for detecting deterioration defect of the structural part according to  claim 1 , further comprising:
 comparing the N first actual modal parameters of one of the M first subject structural unit having the deterioration defect to first modal parameter information so as to determine a degree and a position of the deterioration defect when determining the first subject structural unit has the deterioration defect; 
 wherein the first modal parameter information comprises N first comparison modal parameters, each of the N first comparison modal parameters indicates a respective one of the deterioration defect of the position and other deterioration defects of other positions in the first subject structural unit. 
 
     
     
       5. The method for detecting deterioration defect of the structural part according to  claim 4 , wherein each of the N first actual modal parameters of the first subject structural unit having the deterioration defect comprises an amplitude value of a characteristic frequency, each of the N first comparison modal parameters corresponds to a plurality of first deterioration curves, and determining the degree and the position of the deterioration defect comprises comparing each of the amplitude values of the characteristic frequencies to the plurality of first deterioration curves of a respective one of the N first comparison modal parameters, so as to determine the degree and the position of the deterioration defect;
 wherein each of the plurality of first deterioration curves corresponds to a predicted deterioration defect having a deterioration defect value and located in a position of the first subject structural unit having the deterioration defect. 
 
     
     
       6. The method for detecting deterioration defect of the structural part according to  claim 4 , wherein each of the N first actual modal parameters of the first subject structural unit having the deterioration defect comprises a characteristic frequency, each of the N first comparison modal parameters comprises a plurality of second deterioration curves, and determining the degree and the position of the deterioration defect comprises:
 obtaining at least two sets of predicted deterioration defect parameters according to the characteristic frequencies and the plurality of second deterioration curves comprised in the N first comparison modal parameters; and 
 determining the degree and the position of the deterioration defect according to the at least two sets of predicted deterioration defect parameters. 
 
     
     
       7. The method for detecting deterioration defect of the structural part according to  claim 4 , wherein each of the N actual modal parameters of the first subject structural unit having the deterioration defect comprises a characteristic frequency, the characteristic frequency has a first frequency in a first direction and has a second frequency in a second direction, the method for detecting deterioration defect of the structural part further comprise determining a form of the deterioration defect according to the first frequency in the first direction and the second frequency in the second direction. 
     
     
       8. The method for detecting deterioration defect of the structural part according to  claim 7 , wherein determining the form of the deterioration defect according to the first frequency in the first direction and the second frequency in the second direction comprising:
 determining whether the first frequency in the first direction is consistent with the second frequency in the second direction; 
 determining the form of the deterioration defect as a uniform defect when the first frequency in the first direction is consistent with the second frequency in the second direction; and 
 determining the form of the deterioration defect as a partial defect when the first frequency in the first direction is not consistent with the second frequency in the second direction.